Katie has been described as being 5ft 4in, of slim build, with long, dark brown hair and light brown coloured eyes. It is believed she is wearing a green parka coat with a brown/grey fur hood, blue skinny jeans and red and white baseball boots.

Karl has been described as being 5ft 9 in, of slim build, with short mousey coloured hair and brown eyes. He is believed to be wearing dark-coloured tracksuit bottoms, a grey hooded top and grey ankle boot trainers with a white tick on.

If you have information please call Northamptonshire Police on 101.

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